Chaeles d



(No Model.)

0. D. ROGERS.

WOOD SCREW.

No. 367,011. Patented July 19, 1887.

Elli

UNITED STATns PATENT Orrrcn.

CHARLES D. ROGERS, OF PROVIDENCE, RHODE ISLAND, ASSIGNOR TO THE AMERICAN SCREWV COMPANY, OF SAME PLACE.

WOOD-SCREW.

srncrrrcarron forming part of Letters Patent No. 367,011, dated July 19, 1887.

Application filed November 26, 1886. Serial No. 219,987. (No model.)

T all whom, it may concern: with the head 71, said diameter at 0 being prac- Be it known that I, CHARLES D. ROGERS, a tically the same as the outer diameter of the citizen of the United States, residing at Provi screw-thread, as indicated by the dotted lines. deuce, in the county of Providence and State In Fig. 2 the shank s is represented as being 5 of Rhode Island, have invented certain new slightly concave in the direction ofits length,

and useful Improvements in \Vood Screws; as at s, the diameter thereof at its junction 5 and I do hereby declare the following to be a with the head h being enlarged and correfull, clear, and exact description of the invensponding substantially with the outer diametion, such as will enable others skilled in the ter of the screw-thread t, as just described with .10 art to which it appertains to make and use the reference to Fig. 1. In Fig. 3 the shank s is same, reference being had to the accompanyshown as being slightly convex in the direc- 1mg drawings, and to letters or figures of reftion of its length, as at 8*. erence marked thereon, which form apart of. The head It may be of any desired form, as

this specification. usual,-and have a nick, a, or its equivalent 1 This invention relates to improvements in therein, by means of which the screw is .wood-screws, so called, and consists, essenadapted to be axially turned.

tially, in the novel construction of the shank The advantage possessed by a screw having or stem contiguous to the head. my improved shank s is, that the screw is much The object of my present invention is to stiffer and stronger than one wherein the shank 2 produce a stronger wood-screw than heretois of uniform diameter throughout at the core.

fore. To this end the diameter of the core of Having thus described myinvention, what I 7:) the screw, at the commencement of the screwclaim as new, and desire to secure by Letters thread, is made to gradually increase up to its Patent of the United States, isintersection with the head, thereby forming a 1. The wood-screw hereinbefore described,

2 conical (or substantially so) shank or plain having the unthreaded shank portion thereof portion, all as will be more fully hereinafter which connects the head and the screwset forth and claimed. threaded portion extending rearwardly from In the accompanying drawings, Figure 1 the core of the screw in a divergent direction, represents a perspective view of my improved substantially as shown and set forth.

30 woodscrew, enlarged, and Figs. 2 and 3 rep- 2. The improved wood-screw hereinbefore resent similar views of the plain shank pordescribed, the same consisting of a screwtion and head, having a slightlymodified outthreaded portion terminating in a sharpened line. point, a head adaptedto receive a screw- The following is a more detailed description driver, and a tapering or cone-shaped shank 35 of the invention: connectingsaid head and screw-threaded por- A indicates the improved wood-screw as a tion, substantially as shown and set forth. whole, the convolutions of the screwthread t, 3. The improved woodscrew having the the core 0, and the screw-threaded point p bediameter of the shank at the intersection with ing substantially as usual, said screw-thread the head substantially the same-as the outer 40 being produced by the rolling process, indiameter of the screw-thread and tapering volving the use of dies, a description of mechtherefrom in a decreasing ratio to the root or anism for the purpose not being deemed essencore of the thread, for the purpose hereinbe tial to this specification. fore set forth.

The novelty in the wood-screw illustrated In testimony whereof I have affixed my sig- 5 herewith consists in the peculiar form of the nature in presence of two witnesses.

unthreaded shank portion s, the same com- CHARLES D. ROGERS. mencing at the screw-thread t at the point 0, Vitnesses:

and extends rearwardly in an increasing di- NM. R. DUTEMPLE,

ameter up to the point of its intersection, c, G120. H. REMINGTON. 

